007 What is an Action Potential

This is the first in my new video format and I really hope you enjoy it.

Once you have finished watching the video, go ahead and leave your comments below.

If you have any questions, that would be the place to ask them.

- Leslie Samuel

Transcript Of Today’s Video

Welcome to another episode of Interactive Biology TV. My name is Leslie Samuel. In this video, I’m going to be answering one basic question: What is an action potential? You’re probably going to notice that it’s a little different than the 6 episodes that I’ve done before. And the 2 main differences that you’re going to notice are:

I no longer call it BioVid. The reason for that is “Biovid” doesn’t really tell what this is all about. I’ve changed it to Interactive Biology TV, because it’s going to be interactive, it’s going to be about biology, and it’s going to be a video. So from now on, you’re going to hear me say “Interactive Biology TV” as opposed to “BioVid.”

You’re going to notice that I’m on camera this time, and that’s a little different because in the past, I’ve done slides and animations and so on. The reason I’m making this change is basically because I wanted to do something that I can produce much quickly. In the last year, I only made 6 episodes, and I want to be doing episodes on a regular basis and this is just easier for me to produce and I can put together a relatively professional-quality video in a short period of time.

I hope you enjoy this new format. Please let me know in the comments below, and if you have questions or comments about it, you can just do that. It’s going to be relatively laid-back and I’m just going to be talking to you about these different concepts.

So, let’s get into the content for today. Today, I’m answering the question “What is an action potential?” If you’ve looked at any of the previous episodes, you’ve seen that I’ve given an introduction to the nervous system and to neurons. That introduction to neurons basically comes right before this in terms of understanding the concepts, the different parts of the neuron.

Now, the main part of the neuron that we’re going to be talking about today is the axon. I have a very amazing device here that I’m going to be using to illustrate that. The axon is the part that sends the signal. A signal starts in the soma, there’s processing that happens in the soma, and we’re going to talk about that later on. It sends a signal via the axon, to the ends of the axon, the axon terminals, and then that signal can basically go to the next neuron.

How I’m going to illustrate this is really simple. If someone touches your hand, you feel it. And the reason you feel it is because there are signals that start at that point, and the signals go to your spinal cord, and then up to your brain. These are electrical signals that happen relatively quickly, so that your brain can interpret that stimulation, and your brain tells you “Okay, someone is touching you.”

That is an action potential. You can call it an action potential, you can also call it a nerve impulse, but it’s basically that electrical signal that goes from that stimulation point all the way to the brain. And these signals are going on throughout the body, doing a bunch of different things, and we’re going to talk about that.

So, here we have my handy-dandy iPhone 4. I’m going to turn it on. And I have my earbuds, I’m going to put these on. I’m assuming you guys know how this works, but the iPhone 4 is an amazing device. It has built-in an iPod, and I’m going to assume you know what an iPod is. You know what, I’m going to tell you what an iPod is, just for some strange reason you don’t know what an that is. It’s an MP3 player that allows you to play music and audio books and a whole bunch of other stuff.

Anyhow, I’m going to stimulate this iPhone, and it’s going to send an electrical signal via this cable to the earbuds, and we’re going to assume as if it’s going to my brain. And it is going to my brain. So, here we have a cable sending signals, and then there can be a response. The brain can interpret that stimulation. Okay, so I’m going to press Play, and this is me stimulating. And as soon as I press Play, I can hear music. I can dance to the music, I can do a whole bunch of stuff. Let me stop that for now.

But basically, here we have that wire, and these are the axons of the neurons sending signals to the brain, to different parts of the body. It’s basically how the nervous system communicates with the different cells and organs and the glands. So, really simple, the action potential is that signal that goes through the axons along the nerves and basically takes a signal from one place to another place, whether that’s from the brain to my hand that pulls away, whether it’s from the stimulation point all the way to my brain.

I hope that makes sense for you. That’s basically what an action potential is. If you have any questions, comments, leave it below in the comments field. I’d be happy to follow up and answer your questions, or even make a video about it. That’s it for this episode, and I’ll see you on the next one.

This is a really simple video. You do not go through the sodium/potassium pumps, depolarization, refractory period nor resting state. This are core topics that average biology students would learn so please make videos about these.

My lecturer's notes and explanations are a mess, missing basic information and the notes not even referring to the meanings of some acronyms she uses. With my exam around the corner and none of what my lecturer says making sense i'm in a lot of trouble. Fortunately a friend pointed me to your videos which is really helping me out a lot and I could definitely use any help I can get.
I really appreciate these videos as they're of tremendous help. Thanks a lot!